Standardized FDG uptake as a prognostic variable and as a predictor of incomplete cytoreduction in primary advanced ovarian cancer

Abstract

Introduction. In patients with advanced ovarian cancer undergoing preoperative PET/CT, we investigated the prognostic value of SUV in the primary tumor and we evaluated the value of SUV for predicting incomplete primary cytoreduction (macroscopic residual tumor). Material and methods. From September 2004 to August 2007, 201 consecutive patients with a pelvic tumor and a Risk of Malignancy Index (RMI) > 150 based on serum CA-125, ultrasound examinations and menopausal state, underwent PET/CT within two weeks prior to standard surgery/debulking of a pelvic tumor. At two-year follow-up (August 15, 2009) the association between SUV and overall survival/cytoreductive result were analyzed in 60 ovarian cancer patients (58 stage III and two stage IV). Results. At inclusion median age was 62 years (range 35–85 years); 97% (58/60) had a performance status ≤2; 42% (25/60) underwent complete debulking (no macroscopic residual tumor); median SUVmax was 13.5 (range 2.5–39.0). Median follow-up was 30.2 months. At follow-up 57% (34/60) were alive and 43% (26/60) had died from ovarian cancer. SUVmax in patients alive was not statistically different from SUVmax in dead patients (p=0.69), and SUVmax was not correlated with the amount of residual tumor after surgery (p=0.19). Using univariate Cox regression analysis, residual tumor was a significant prognostic variable (p=0.001); SUVmax was not a statistically significant prognostic variable (p=0.86). Discussion. FDG uptake (SUVmax) in the primary tumor of patients with advanced ovarian cancer was not a prognostic variable and the FDG uptake did not predict complete cytoreduction after primary surgery. Future prospective clinical trials will need to clarify if other PET tracers can serve as prognostic variables in ovarian cancer.